Both men told a White House news conference that the risk to the American people remained very low.

The announcement came as new cases of Covid-19, the infection caused by the Wuhan coronavirus, continue to spread at a rapid pace around the world.

Sixty cases have so far been reported in the US.

Minutes after the White House news conference, the authorities confirmed another US case of Covid-19.

Addressing the press, Mr Trump expressed confidence that the US would be able to handle coronavirus.

"We're very, very ready for this," Mr Trump said. Researchers were "rapidly developing" a vaccine, he said.